PROJECT SUMMARY (Supplement) Psychiatric genetics researchers have recently identified numerous genomic loci associated with schizophrenia, depression, autism spectrum disorder, bipolar disorder, attention deficit hyperactivity disorder, and other disorders. The identification of these genomic loci makes it possible to generate polygenic risk scores (PRS) to stratify an individual?s risk for different psychiatric disorders compared to the general population. The usual age of onset for most psychiatric disorders is during childhood, late adolescence, and early adulthood. As many as 20% of children and adolescents in the U.S. have a diagnosable psychiatric disorder. Numerous studies suggest that early intervention improves clinical outcomes, however, the average duration of untreated symptoms and disorders is generally in the order of years. Thus, there is great need for tools such as PRS to help improve the identification of children and adolescents at higher risk for psychiatric disorders in order to take steps to potentially prevent or delay the onset of disease, minimize morbidity and risk for suicide, or provide early intervention. The promise of reliable PRS in mental health care and prevention is considerable, but there are critical potential ethical and policy challenges. For example: which children and adolescents, if any, should be tested; when, if at all, should children and adolescents be tested; where should they be tested; should PRS testing require a clinician?s order or could it be done through direct-to-consumer services; who should have access to children and adolescents? psychiatric PRS results; how should these results be used; what kind of impact would PRS results have on children and adolescents who are at increased risk; how may high PRS impact parents/guardians? expectations and parenting practices; would PRS exacerbate or decrease mental health stigma and self-stigma for those identified to be at higher risk? The long-term goal of this research is to develop ethically-justified and empirically-informed guidelines and tools to address the ethical and policy challenges raised by the use of psychiatric PRS with children and adolescents. The objective of this supplement, which is the first step in pursuit of this goal, is to identify child and adolescent psychiatrists? knowledge, practices, attitudes, expectations, and perceived benefits and risks about the use of psychiatric PRS. To achieve this objective, we will first use the Delphi technique with expert child and adolescent psychiatrists to develop the ?PRS in Child and Adolescent Psychiatry Survey.? Then, we will administer the survey to child and adolescent psychiatrists and examine correlates of outcomes. Next steps include developing an R01 application to more comprehensively examine ethical principles and develop ethically-justified guidelines to promote the responsible use of psychiatric PRS with children and adolescents.